Igniting plug for hand grenades



Sept. 8, 1936- LAGUESSE 2,053,836

IGNITING PLUG FOR HAND GRENADES Filed April 15, 1935 @SSQ. 77 Lagu Patented Sept. 8, 1936 PATENT OF F] C E IGNITING PLUG FOR HAND GRENADES Fernand Laguesse, Herstal, near Liege, Belgium Application April 15, 1935, Serial No. 16,505 In Belgium April 18, 1934 4 Claims.

In theknown handgrenades the control of the percussion is generally obtained by means of a catch leveror rod which tends to move away from the body'df the grenade under the action of the percussion spring, and is held in the safety positionby .a pin or other equivalent member. Consequently in such grenades, the percussion takes place, after the safety device has been removed the catch lever is released'whether the grenade is It is, therefore, necessary to throw the grenade as soon as the pin holding the catchlever has been removed, but although the time to burn is about five seconds for the wick, ignited by the 5 striker premature explosions have often occurred which have given rise to very serious accidents.

The object of the present invention is to increase the safety with which hand grenades can be manipulated by providing them with an igniting plug, the striker of which is liberated by a catch lever or an equivalent member only after the latter has effected a movement of fairly large amplitude, say for example a quarter of a turn, without this displacement influencing in any way 25 the degree of tension of the striker spring.

Consequently as the catch lever is in no way urged by the striker spring to make this displacement, it remains in stable equilibrium in all the positions of large amplitude prior to the percus- 30 sion proper.

This displacement will be produced either under the effect of a removal or by a ballistic action, for example, under the action of inertia, centrifugal force, etc.

35 If, in the usual manner, use is made of a pivoting catch lever, the displacement which is intended to retard the percussion when the grenade is thrown, is obtained by combining circular co-opcrating surfaces, one of which forms a track for 40 the other, these surfaces being carried respectively by a catch lever and by an igniting plug or a member rigid therewith, so that the axis joining the centres of these surfaces passes through the 45 centre of rotation of the catch lever.

Further, in order to seal the internal part of the grenade in a perfectly fluid tight manner, the tail of the striker is gripped in a sliding cover or cap engaged by the catch lever and applied her- 50 metically upon the upper face of the igniting plug by the striker spring.

One embodiment of an igniting plug according to the invention is illustrated by way of nonlimiting example in the accompanying drawing,

inwhichz- Figure 1 is a partial longitudinal section of the plug.

Figure 2 is a partial front view thereof.

Figure 3 is a plan view with an oblique section through the catch lever. 5 ,As in the known hand grenades, the body I of the plug is screwed upon the body of the hand grenade and comprises the exploder holder 2, carrying the priming cap 3, the relay 4 and the detonator 5.

In the body I issuspended the striker 6 having a spherical head and a. conical shaped part I which bears upon a correspondingly shaped wall of a chamber II' formed in a cover or cap Il mounted upon the body with the interposition of 5 a joint I2.

The conical tail 7 is gripped between the edge 9 of the body I and the edge In of the chamber II of the cover or cap II.

The spring 8 seated on an annular shoulder in the hollow of the body I exerts a pressure upon the striker I which also has the eflect of pressing the cover or cap I I tightly against the upper face of the body I and of urging it at the same time to slide towards the left. But the cover I I is locked in the cooked position by a catch lever I! which encloses the cover, and has upon each of its lateral faces a beak or hook I8 adapted to engage a lug I9 rigid with the cover or cap II (Figure 3).

The line aa joining the points of contact a of the hook l8 with the lugs I9 constitutes the pivoting axis of the lever ll.

Furthermore, the body I is provided externally with a circular surface 20 having its centre on the line aa (Figure 3) and forming a track for a roller 2| pivoted at 1) upon the lever Il. As the straight line ab connecting the centres of the arcuate surface 20 and of the roller 2| together cuts the axis of rotation of the lever I'I centrally, the lat- 40 ter is constantly in stable equilibrium as long as the roller 2| is in contact with the surface 20.

A pin I6 locks the lever I1 in known manner in order to permit the grenade to be handled with safety.

Under these conditions, when the grenade is thrown after withdrawing the pin I6, the lever I1, under the action of centrifugal force pivots about the axis am and moves further and further from the body of the grenade, its roller 2| running on the track 20 for a quarter of a turn, for example, until it finally leaves the curve 20. At this moment the lever I1 is thrown out of balance and is pulled off the grenade so that it liberates the cover which then moves to the left under the action of The centrifugal displacement of the lever I1 is facilitated by the presence of a mass 22 fixed at its end.

As stated above numerous constructional modifications of the igniting plug according to the invention may be imagined; for example; the

'roller 2| may be mounted on'the body I of the ,plug,while the circular surface 20 will be provided upon or in the catch lever l1.

"What I claim is:

'1. In an igniting plug for hand'glfenadi s, a

,sliding cover'adapted to obturate the body of the Plus, said cover having a chamber formed therein, a spring pressed striker mounted in said plug body and having a conical upper part gripped, in its cocked position in the said chamber, between an edge of said cover within said chamber andan edge of theplug body, the spring, pressing on the striker to cause the firing of the primer acting also to apply hermeticallythe sliding cover against the plug body in the cocked position of the striker. 1

2. Inran igniting plug for hand grenades, a sliding cover adapted to obturate the body of the 'plug a chamber internally formed in saidcover,

a spring pressed striker mounted in said plug body and having a conical upper part'gripped in its cocked position in the said chamber between an edge of said cover'within said chamber and an 7 the spring 8, and permits the striker 6 also to re- 7 spond to the pressure of the spring 8 and fire the primer 3.

edge of the plug body, a catch member locked on the plug body by a safety pin, and adapted to enclose with its upper part the sliding cover, said catch member having notches cooperating with lugs providedon said sliding cover to hold the catch member in the cocked position, a. circular surface formed externally on the plug body and constituting a track, and a revoluble member carried by the catch member engaged by said track.

3. An ignition plug for hand grenades comprising a body member having an ignition chamber open at one end and containing a priming cap, an annular ledge adjacent said opening, a hollow cap covering said opening and provided with a bevelled edge near its center, a striker having an enlarged head and a cone-shaped tail adapted to engage between said bevelled edge of the cap and said ledge in asse'mbledposition, a double acting spring inserted between said ledge and said striker head, whereby said striker isheld in cocked posi- 

